Electrical system



A. L. HARVEY AND G. W. HU'EY.

ELECTIJCAL SYSTEM.

APPUCATiOH FILED MA. 8. 1911..

Patenteii June 14, 1921.

WH'NESSES'.

INVENTORS All: erfLHdifVPY d'eorgewflwy ssrr es I MTEN masses QC'EFQRATIQN OE PENNEYL'VANIA.

MAYLVEY AND GEfiR-GEW'. l-I'UEY, 0F HILKINEEURG, PENNSYLVANIA, ASSHi-IIOR 'llI W EETINGHOIJ'SE ELEGTRIC AND MANUIEACTURlN'G GOMPB NY, A.

ELECTRICAL SYSTEM.

l jfilglfif e Application filed March 8,

To all whom it may concern.

Be it known that We, ALBERT ll. HARVEY, a cilzizen of the United States, and a resident of Wilkinsburg in. the counay of Allegheny and 53mm of lennsylvamie, sncl Gnome W. Hour, a citizen of the United States, and e resident of ll ilkinsburg in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Electrical Systems, of which the following is a specification Um? invention relates to electrical systems, and. itbss for its object to provide an air rengement whereby ilie circuits 0% electric motors are coritrolleil in accordance with conditions obtaining therein.

In the operation of electric motors, it may occur that one of the line conductors may be broken or that, for some other reason, there is a failure of voltage upon one or more coni'lii are PJTOlZQClJlVE5ilBVlCQS for alternatingcm, t motors usually provided with so lusting soils which are coimecleil. belween lWo of the line eoiidimizers of pelypliese Cir-- culls. /Vb'en such 51 managements are em ployeol is is possible ilml, under certain conditions, any one of the line conductors may be broken without causing the protective devic to open the motor circuit,

In the arrangement em strucleil in sccordsnce with our inventiom the co merrtio between the source of energy and the mosor controlled by manually operable pusly button swiliehes and an electromagnetic line switch, The circuit of the actuating coil of "lube eleelxroiiisgriesic line sWi'lZcb controlled by relays which eorresponcl in mu her, to lbs 1 conductors The aesuetlzi coilsol' ills relays in series with the ETGS JQCllYD eomiizctors of the Cll'Cllllj to be proleclezl. Lech of the relays is responsive, filler-shire, ls mirreiil; eoiiclitioiis ob'leining in the correspoiidiiig line oomluctor and. to failure of voltage in Lille corresponding phase. The l switch opened automatically upon the milure voltage in one or more of the line conductors. i

the accompanying drawing, the single ii are is s i'liagrsmmsfieyiew of circuits em. solvers tiis embodying our invention.

Line coiicliiel ors l, 2 and 3, which. may be ooisnecterl any suitable source of threeplmse sl errietiiigcurrentelectromoiive supply energy to an elternetiuge r v Specification of Letters Patent. Paijgggi ggl June 14 191?; Serial 1%. 152,391.

rent motor The motor may be opera? lively connected to any suiieble mechanical loud. The motor circuits are controlled by a manually operable switch 5 11ml an elecl-roinag'neticelly operable line switch 6 lizw mg; an actuating coil Ts. I

The circuit of the coil 7 is controlled by puslbbuttonswitches 8 and 9 that are pro virled with zrppropriste legends fOlklGEl listing their functions The circuits of- 16 coil 7 is controlled, also by overload r y 10 and. by e relay 11 the, is controlled in s msnnegrbto be described.

lhe relayll is provided with as. actuating coil 12, the circuit of which is controlled by three underloecl relays 1,8 having actuating coils thrill; are in series with the respective phase windings of the motor, The coils 14 are arranged to maiiitein the corresponding relays in their upper positions for fall values of currents obtaining during elk, operation of the motor from. zero load to full load, under normal conditions. The relays are permitted to close however, upon the occurrence oi: failure of voltage-iii the corresoonding phases oil the cicuit since in such the current traversing the phases thus aflecled is. to zero value. This Arrange mem 1). .le by reason of the feet that the current silken by an induction motor is relatively li s-ivy :ii zero loml.

Each of the relays 13 is mecliem slly con- "the coil 15 is energised aiirl the core member 16 is (lrmrn upwardly, the relays 123 are per mittecl to fall to their closeil positioi'is if the coils Ll are values.

To start the motor, the main s viieli 5 is elos Ll and the push lHllllUll swilcl actuirked to ll closed position and lielrl llie're m0- nicnmr A. circuit is completed which extends E' .1 e eoiioluctor 18, which may be connected to any suitable source of either direct-or slternsling curricula .ihmugh nush ing an electric motor and a switch, of means for controlling said switch in accordance with the respective values of the currents traversing said circuit, said means compris mg a plurality of relays having coils respectively in circuit with the phase windings of said motor and mechanical means for rendering said relays inoperative when said switch is in its open position.

8, In an electrical system, the combination with an alternatingcurrent circuit compris ing an electric motor and a switch, of means for controlling said switch in accordance with the respective values of the currents traversingisaid circuit, said means comprising a plurality of relays having coils respectively in circuit with the'phase windings of said motor, an .electromagnet having a lost-motion connection to said relays for rendering them inoperative when the motor circuit is open and for permitting them to operate under redetermined conditions when the motor circuit is closed.

9. In an electrical system, the combination with an alternating-current circuit compris ing an electric motor and a switch, of means for controlling said switch inaccordance with the respective values of the currents traversing said circuit, said meanscompris" ing a plurality of relays having coils respectively in circuit with the phase windings of said motor, a circuit independent of the motor circuits and comprising an actuating coil for-said switch, a switch for controlling the circuit of said coil, and means for opening the circuit of said actuating iwil upon the closing of any of said relays, independently of the position of said controlling switch. 10 rn v'cleetrical system, the combinaf h an electric motor and a electromagnetic switch for controlling tl circuits of said motor, of an electric circuit inde-' sea 13 pendent of the motor circuitoand comprising an actuating end for said ,SjW1tCh, 2t manually operable switch for contgeiling the circuit of said coil, and means operable independently of the position of said manually ope!" able switch for opening the circuit of said coil upon the occurrence oi abnormal con ditions in said motor circuits, l

11. In a motor-control system, the com bination with an electric motor and a switch device for controlling the circuits of said motor, ofa manually operable switch tor" initiating the operation of said switching device, and means comprising a plurality of relays controlled by circuit conditions for effecting the operation of said switching de vice to open the motor circuits independ ently of the position of said manually operable switch.

12. In an electrical system, the combine tion with an electric circuit, of coi'itrolling switch therefor, an actuating coil for closing said switch, a normally closed relay for con trolling the circuit of said coil and a second.

relay for opening said normally closed relay 1917. ALBERT L. HARVEY.

chosen w. near. 

